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%I
%S 2,3203,5323,75323,11753221,131175329,171311753203,19171311753229,
%T 231917131175321,292319171311753231,3129231917131175327,
%U 3731292319171311753239,41373129231917131175321
%N Smallest prime whose decimal expansion begins with concatenation of first n primes in descending order.
%C (1) Sequence is conjectured to be infinite
%C (2) a(n) ="p(n)...p(1) R(n)"
%C (3) R(n) for n>1: "03", 3, 3, 21, 9, "03", 29, 1, 31, 7, 39, 1, 33, 69, 23, 3, 59, 27, ...
%C (4) It is conjectured that R(n)=1 for infinite many n
%D Leonard E. Dickson: History of the Theory of numbers, vol. I, Dover Publications 2005
%e a(1)=2=prime(1) is the exceptional case, because no R(1)
%e a(2)=3203=prime(453) = "32 03", R(2)="03"
%e a(5)=11753221=prime(772902) = "p(5)...p(1) 21", R(5)=21
%Y Cf. A000040, A066065, A019518, A089710, A053546
%K nonn,base
%O 1,1
%A Ulrich Krug (leuchtfeuer37(AT)gmx.de), Dec 04 2009
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